1. Field of the Disclosure
The present invention concerns the field of communication; it relates to an apparatus for operating a read/writer, comprising an antenna and a read/write unit, for communication with an identification medium via a communication link. The invention also relates to a method for operating this apparatus.
2. Related Art
WO2004/105157A2 discloses a method and an apparatus for contactlessly supplying power to an energy storage appliance by means of radio frequency (RF). The apparatus comprises three units: a base station, a reception station with an antenna and an energy storage appliance, which is connected to the reception station. In line with the method disclosed here, the reception station is contactlessly supplied with power by means of the base station, the RF power received via the antenna is converted into a DC voltage and the energy storage appliance is charged.
WO2006/007418A1 describes a first appliance having a first antenna and a first supply and a second appliance having a second antenna and a second supply, where the appliances communicate with one another contactlessly by means of an RF signal. The first or second appliance additionally has a third antenna for communication with a third appliance. The first and/or the second antenna has/have a first and/or a second power drawing component connected to it/them for the purpose of supplying power to the first and/or the second supply. During communication between the two appliances, it is possible to arrange that, by way of example, the first appliance, having a relatively low charge state for the supply, is loaded by virtue of the first power drawing component of the first appliance using the first antenna to draw the power from the RF signal emitted by the second appliance. The drawing of power is initiated by the user, following the communication between the two appliances or at the start of the communication between the two appliances. The power is drawn either in parallel with or sequentially to the communication between the two appliances, for example by virtue of different RF frequencies being used for the communication or the power transmission. The drawing of power by the first appliance may be dependent on approval by the user of the second appliance or on the first appliance, possibly following a request to the second appliance, receiving an unmodulated RF signal from the second appliance which is not used for communication.
The prior art admittedly reveals how wirelessly interconnected appliances which, in a normal operating state, have autonomous or mutually independent interaction with third-party appliances can supply one another with power. At any rate, in the event of a partial or total loss of charge from a storage battery in one of the connected appliances, its storage battery is charged, with partial or complete functionality of the latter appliance also being made possible. The external power supply for the second appliance therefore always accesses the supply unit of the first appliance, charges it and furthermore produces or ensures partial or complete functionality of the second appliance.
By contrast, no account is taken of the fact that not only is it possible for a supply unit for an appliance to have a low or inadequate charge state—in short to have a charge state: storage battery flat—but also there may be an electrical malfunction in a supply unit too. By way of example, the supply unit may be unchargeable or may have a short circuit, an electrical line interruption or another electrical fault (overvoltage or wiring error in the case of direct mains connection). In such cases, too, conventional knowledge according to the state of the art teaches the practice of making an attempt to charge an appliance without evaluating or taking account of the possible consequences (overheating, fire damage, damage to further components). Regardless of these problems, a conventional appliance acts upon an inoperable appliance which is close enough for operative connection by supplying it with charging power and possibly allowing an operating state.